Display licenses of bundeled code

[diegoiast]

In AppImage we can:

#include <QDir>
#include <QFile>
#include <QHash>
#include <QRegularExpression>
#include <QTextStream>

QHash<QString, QString> buildLicenseHash(const QString &docRoot)
{
    QHash<QString, QString> result;

    QDir dir(docRoot);
    QStringList packages = dir.entryList(QDir::Dirs | QDir::NoDotAndDotDot);

    for (const QString &pkg : packages) {

        QString copyrightFile =
            docRoot + "/" + pkg + "/copyright";

        if (QFile::exists(copyrightFile)) {
            QString license = extractLicense(copyrightFile);
            result.insert(pkg, license);
        }
    }

    return result;
}

QString extractLicense(const QString &filePath)
{
    QFile file(filePath);
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return {};

    QTextStream in(&file);

    QRegularExpression re(R"(^License:\s*(.+))");

    while (!in.atEnd()) {
        QString line = in.readLine();
        auto match = re.match(line);
        if (match.hasMatch()) {
            return match.captured(1).trimmed();
        }
    }

    return "Unknown";
}

No idea about win32, not macos.